Knitting machine and process



Get. 12 1926.

A. STEWART I KNITTING MACHINE AND PROCESS Filed July 17. 1925 3 Sheets-Sheet 1 /N VENTOR TTOENE Oct. 12 1926.

A. E. S TEWART KNITTING MACHINE AND PROCESS Filed July 17. 1925 3 Sheets-Sheet 2 Q W ATTORNEY Oct. 12 ,1926. 1,602,786

A. E. STEWART KNITTING MACHINE AND PROCESS Filed July 17. 1925 5 Sheets-Sheet 5 I B I 10 I 4 //v l/EN TO}? 8 Muff, 5224M I, ATTOR/VE Patented Oct. 12, 1926.

UNITED STATES PATENT OFFICE.

ALBERT E. STEWART, OF FRANKLDT, NEW'HAMPSHIBE, ASSIGNOR TO ACME KNIT- I TING MACHINE 6'0 NEEDLE COMPANY OF FRANKLIN, NEW HAMPSHIRE, A GOR- IPORATION OF NEW HAMPSHIRE.

KNITTING MACHINE PROCESS.

Application filed my 11, 1925. Serial. No. 44,215.

This invention relates to the knitting of fancy fabrics, and more especially to the production of stripes in plaited fabrics.

Such fabrics are knit from two or more v threads, differing in color or.other= characteristics, one or another of these threads appearing at the face of the work as required to produce the desired pattern or color-effect.

The making of narrow vertical stripes in knit fabrics has been a very troublesome matter. It is impractical machine knitting to make such stripes by a thread changing operation, and this result has usually 5 been accomplished heretofore by so manipulating the needlessand the threads as to cause one of the threads to dodge the needles at the points where the striped effect is desired. This process obviously producesa fabric in which thestitches are weaker in the stripes than in the remainder of the fabric. Moreover, the mechanisms required for this pur pose are relatively complicated and liable to get out of order, with the consequent interruption of production.

I have discovered that these difficulties can be avoided and the results sought produced v by reversing the threads in the 'loops' of those portions of the fabric where stripes are desired, and that such reversal can be effected by properly tensioning the threads and guiding them during the oop forming operation.

Themanner in which this result is accomplished and a convenient mechanism for performing the required operations will be understood from the following description when read in connection with the accompanying drawings, and the novel features will be particularly pointed out in the appended claims.

In the drawings Figure 1 is a plan view, with certain parts broken away, showing those parts of a knitting machine head with which the present invention is more especially concerned;

Fig. 2 is a view, partly inside elevation and partly in vertical cross-section, of the mechanism shown in Fig. 1;

Fig. 3 isa diagrammatic view illustrating certain steps in the stitch forming operation; Fig. 4 is a perspective view illustrating the relative positions of certain of the parts during the forming of the stitches;

Fig. 5 is a side elevation of one of the sinkers shown in Fig. 4 and a needle cooperatlng therewith;

Fig. 6 is a similar view of a special sinker lncluded in the mechanism shown in Fig. 4;

Fig. 7 is a side elevation of a portion of one of the regularsinkers with threads of a loodp resting on the shoulder of the sinker; an

Figs. 8, 9 and 10. are diagrammatic views showing the manner in which one of the special sinkers guides the threads of a loop 1n reversing them.

The machine shown comprises a needle cylinder 2 carrying a series of needles 3 which are arranged to be operated by the usual cams, one of which is shown in Fig. 2 at 4. A sinker ring 5 supports a series of sinkers which alternate with the needles 3. These sinkers have-butts runnin in a cam track 6 of a circular sinker ring all these parts being constructed, arranged, and operated in the usual manner. The machine shown is of the revolving cylinder type, but the invention is equally applicable to other types of knitting machines.

Most of the individual sinkers of the series shown are of the construction best illusoverhanging said shoulders, and also haveshort butts 9 to run in the cam groove 6. Interspersed with'these sinkers, which may be referred to as the regular sinkers, are special sinkers 10 of the construction best shown in Fig. 6, the latter sinkers being located at the point or points where it is desired to form a stripe or stripes in the fabric. These sinkers have longer butts 11 which also run in the groove 6. As the sinkers approach the point in their orbit at which the needles take the thread, they are all forced outwardly by a cam 12, Fig. 1. After the needles have taken the thread and while they are drawing the bights of thread down over" by the engageauxiliary cam is pivoted on the screw 45, Fig. 1, anda spring 46 tends to hold it in an outward or inactive=position. \Vhile the cam is in this position the special sinkers are not moved inwardly until their butts 11 strike the cam 13. In other words, both the regular and special sinkers move in unison.

In order to move the auxiliary cam into or out of its operative position, as desired, a U-shaped arm 15, Figs. 1 and 2, is arranged to bear against the auxiliary cam 14 and is clamped in'a bar 17 by means of a screw 16. This bar is mounted horizontally in a bifurcated arm 18 which is secured on a rock shaft 19. A lever 20, also secured on this rock shaft, carries a screw 21 which bears against a part of the bar 17 Another' part 23 of this lever 20 is arranged to'be engaged'by a cam 24 which is secured on one of the pattern drums 25 of the machine. Consequently, when the lever 23 is operated by the cam 24, the arm 15 is moved toward the left, Fig. 2, thus forcing the auxiliary cam 14 inwardly and holding it in its operative position. As soon, however,as the part 23 ridesoff the cam 24, the. sprin 46 will move the auxiliary cam 14 outwardly again into its inactive or inoperative position.

The'thread or 'yarn (herein referred to as thread) is fed to the needles 3 through thread guides or fingers 27 and 28, respectively, of a usual construction. Since two threads only are ordinarily-used in knitting glaite'd work, only 'two are shown in the rawings, it being understood that more threads may be-used if desired. For purposes of description it may be assumed that one of these threads B is black and the other W is white. A diiferential. tension is maintained on these threads by any suitable tensioning mechanism. As shown, a considerable tension is placed on the black thread 13 by a tension mechanism 30.0f the common disk type,.whi1e the other thread W is allowedto run as freely as possible, it being understood that the difference in' tension maintained on the threads will vary with the nature of the threads and other operating conditions.

I have found that with such an arrangement as that shown, as each needle takes the threads and draws them down over the shoulders ofthe sinkers, both threads crowd against the shank of one or more of the needles immediately behind the rearniost needle which is just pulling the threads over a sinker shoulder. This crowding action i is due to the fact that the needles are revolving about an axis, and will be understood from an inspection of Fig. 1, the needles taking the threads as they do ordinarily in a machine of the type shown. The

thread.B being under considerable tension while the thread W is relatively freeor loose, crowds the latter thread toward the outer side of the. needle cylinder, and the' for example, in Figs-:3 and 4. The relative positions of the threads is clearly shown in Figs. 5 and 7. It will be evident, therefore, that so long as the knitting operation prooeeds in the manner above described, a plaited fabric will be produced having a substantially black outer surface and a substantially white inner surface, the fabric at the knitting point being inside out.

I have found that if during stages of the stitch forming operation a device is pressed against the sides of the thread opposite to the shank of the needle hook, the threads can be reversed. While such a device could be independent of the sinkers, it is more convenient to use a sinker for this purpose. The reversing of the threads is facilitated by making this sinker of somewhat dif'ferent shape from the regular sinkers and, consequently, the special sinkers an inspection of Figs. 4 and 6 that each of these special sinkers has a substantially horizontal web supporting shoulder '32, like the regular sinkers, and that zit also has a work engaging face 33 inclined'fupwardlv 10 have been provided. It will be seen from the 7 initial at a considerable angle with reference to the shoulder.

Fig. 6 shows a needle 3 moving down toward the shoulder 32 of the sinker 1O with As the needlethread Bhas crowded the loose thread W to the inner side of the'sinker loop. If a single special sinker isused .at this point the wale formed by this sinker in the finished fabricwill be white so that a very narrow white vertical stripe will appear on the black face of the goods. If a wider stripe is desired a greater number of special sinkers are used side by side.

It will now be evident 1 hat according to this process a greater tension is maintained on one thread than the other as they are fed to the needles, and this difference in tension is utilized to control the relative positions which the threads take in the knitted fabric. Or, to state the matter somewhat differently, the greater tension, maintained on one thread is utilized in causing it to crowd the loose thread to one side or the other of the tensioned thread, as desired, during the stitch forming operation. During the formation of normal stitches this difference in tension is of advantage in keeping the threads in a definite relationship to each other, but when it is desired to reverse the threads in order to bring a different colored thread to the outer surface of the fabric, the difference in tension is also utilized to produce this result through a proper change in the relative timing of the movements of the sinkers and needles.

Important advantages of this process are the fact that .it can be practiced with very simple and reliable mechanism running at normal speeds. Furthermore, the stitches or loops in which the threads are reversed are practically, if not quite, as strong as the other stitches or loops in the fabric, so that all portions of the fabric are of substantially the same strength. The lengths of the stripes can be controlled by moving the auxiliary cam 14 into or out of its operative position automatically, and the stripes can be made so short that they are, in effect, simply dots. Horizontal stripes can, of course, be made by the usual thread chang ing operations, and consequently, by com bining the two striping processes an almost endlessvariety of patterns can be produced. my invention, what Having thus described I desire to claim as new is 1. That improvement in the process of knitting plaited fabrics which consists in feeding two threads simultaneously to the knitting needles, maintaining a greater tension on one thread than the other during the feeding thereof, and utilizing the difference in tension on the threads to maintain the threads normally in predetermined relative position and to cause the tensioned thread to appear either at the back or front of the fabric, as desired.

2. That improvement in the process of knitting plaited fabrics which consists in feeding two threads simultaneously to the knitting needles, maintaining a considerable tension 'on one thread while allowing the other to run relatively loosely during said feeding operation, and causin the tensioned thread to crowd the loose t read to one side or the other of the tensioned thread, as desired, during the formation of the stitches.

3-. That improvement in the process of forming vertical stripes in knitting plaited fabrics which consists in feeding two threads simultaneously to the knitting needles, maintaining aconsiderable tension steps in the formation of ,4. That improvement in the process of knitting plaited fabrics which consists in feeding two threads simultaneously to the knitting needles, maintaining a greater tension on one thread than the other during the feeding thereof, causing said needles to engage the threads to form loops in said threads, pressing against the threads laterally at one side thereof during the initial normal loops, and reversing the relative positions of said threads incertain of the loops by pressing against the opposite sides of the threads during the initial steps in the formation of the latter loops.

5. That improvement in the proeess of forming stripes in knitting plaited fabrics which consists in feeding two threads simultaneously to a series of needles, causing saidv needles to draw said threads of sinkers and thereby fornf loops in the threads, maintaining a greatertension on one of said threads than the other during the feeding thereof and thereby maintaining the tensioned thread normally at one face of the knitted fabric, threads at certain of the sinkers by causing the latter sinkers to engage the threads at an abnormally early point in the loop forming operation.

6. That improvement in the process of forming stripes in knitting plaited'fabrics which consists in feeding two threads simultaneously to a circular series of needles with one thread above the other, causing said needles to draw said threads over a circular series of sinkers and thereby form loops in the threads, maintaining a considerably greater tension on the upper of said threads than on the lower thread and thereby causover a series I and reversing the sides of the threads opposite to those engaged by the shanks of the needle hooks to reverse said threads in certain of the loops while the stitches are being formed.

7. That improvement-in the .process' of forming stripes in knitting plaited fabrics which consists in feeding two threads simultaneously to a series of needles with one a v A, isoasa thread above the other, causing said needles to draw said threads over a series of sinkers and thereby form loops in the threads,

.maintaining a considerable tension on the upper thread during said feeding operation while allowing the lower thread to feed free ly, whereby the tensioned thread normalliv crowds to one side of each loop, and gui ing the threads during the formation of certain of said loops to cause the tnsioned thread to crowd to the opposite side of the needles draw the, threads downwardly toward the sinkers shoulders.

9. In a knitting machine, the combination of a series of needles, sinkers cooperating with said needles, devices for feeding two threads simultaneously to said needles, means formaintaining a considerable tension on one of said threads while allowing the other thread to feed more freely, special sinkers interspersed with the first mentioned sinkers and having faces to engage and push against said threads, and sinker operating mechanism including means for moving the special sinkers against the threads held by the needles in advance of the other sinkers and while the needles are carrying said threads down to the shoulders of the special sinkers.

10. In a knitting machine, the combination of a series of needles, sinkers cooperat ing with said needles, devices for feeding two threads simultaneously to said needles, means for maintaining a substantially greater tension on one of said threads than the other, cam mechanism for operatin said sinkers to move them toward the big ts of the threads held by the needles, certain of said sinkers having inclined thread engaging surfaces, and an auxiliary cam for moving the latter sinkers into engagement with the threads while the threads are being moved downwardly toward the shoulders of the sinkers. 11. In aknitting machine, the combination of a series of needles, sinkers cooperate ing with said needles, devices for feeding two threads simultaneously to said needles,

means for maintaining a substantially greater tension on. one of said threads than the other, cam mechanism for operatin said sinkers to move them toward the big ts of the thread held by the needles, certain ofsaid sinkers having inclined thread engaging surfaces above the shoulders of the sinkers,-an auxiliary cam for moving the latter sinkers into engagement with the threads while the needles draw the threads downwardly toward the sinker shoulders, and automatic mechanism for moving said auxiliary cam into and out of its operative position.

12. In a knitting machine, the combination of a series of needles, devices for feed ing two threads simultaneously to said needles, means for maintainin a greater tension onone of said threa s than the other, sinkers cooperating with all of said vneedles and includingboth sinkers ofvthe usual type and also special sinkers located at pointswhere vertical stripes are to be made in the fabric, said special sinkers having web supporting shoulders and also having parts above said shoulders for engaging the portions of the threads between the needles as the needles draw the threads down toward said shoulders, cams for operating all of said sinkers in the same time relationship to the movements of the needles, and an auxiliary cam for operating the special sinkers when desired to cause them to engage the threads while the threads are being moved downwardly toward the sinker shoulders.

13. In aknitting machine, the combination of a series of needles, devices for feeding two threads simultaneously to said needles, means for maintaining a greater tension on one of said threads than the other, two sets of sinkers cooperating with said needles and both having the usual shoulders over which the needles draw the loops of thread, one set of said sinkers being provided with the usual beaks overhanging said shoulders and the second set of sinkers each having an upwardly directed thread en aging surface above the shoulder thereo to push laterally against the threads, the sinkers of said second set being located at'points where a vertical stripe is to be made in the fabric, cams for operating all of said sinkers inthe same time relationshi to the movement of the needles, an auxiliary cam ior operating said second set of sinkers to cause them to push laterally a ainst the threads between the needles as t e needles draw the threads downwardly toward; the sinkers shoulders, and means for throwing said auxiliary cam into or out of operation,

as desired.

' V ALBERT E. STEWART.

Certificate of Correction;

- It is hereby certified that in Letters Patent No. 1,602,786, 'ranted October 12,,

1926, upon the application of Albert E. Stewart, of Franklin, l\ew Hampshire, for animprovement in Knitting Machines and'Processes, an error appears in the printed specification requiring correction as follows: Page 3, line 126, claim 6,

7 Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 9th day of November, A. D, 1926.

SEAL WM. A. KINNAN,

Acting Commissioner of Patents.

strike'out the Words while the: stitches are being formed and that the said- 

